How to use
- Count the steps the runner will cover. If the runner also wraps a landing, add that landing length after you calculate, or include it as extra percent.
- Measure one tread and one riser in inches.
- Leave extra length at zero, or type a percent for end turns and pattern match.
- Press Calculate. The hero is feet. Inches are beside it.
How it's calculated
Inches = steps × (tread + riser) × (1 + extra percent ÷ 100). Feet = inches ÷ 12.
The runner width is not an input. A wider runner does not change the length. Square feet of a full-width carpet on the treads is the stair-flooring page.
Worked example
Thirteen steps with a 10 inch tread and a 7.5 inch riser, and no extra, are 13 × 17.5 = 227.5 inches, which is 18.96 feet. Ten percent extra makes that 20.85 feet.
Assumptions
Every step has the tread and riser you typed. A landing, a bullnose, and a starting step with a different profile are not added unless you put them in the extra percent or add their length afterward.
FAQ
Why add the riser?
The runner climbs the riser between treads. A measurement that only adds treads will come up short.
Is this the same as stair flooring?
No. Stair flooring is the square feet of the treads and, separately, the riser faces. A runner is one length.
What if the top step has no riser in the runner?
Reduce the step count, or shorten the result by one riser. The form treats every step as tread plus riser.
Can I enter centimeters?
Not in this form. Convert to inches first. One inch is 2.54 centimeters.